1. Field of the Invention
The present invention relates to an encoded video signal and, more particularly, to a method for broadcasting an encoded video signal and to receiving apparatus for decoding the video signal.
2. Description of the Prior Art
A video signal can be encoded before broadcasting to prevent the use of the video signal unless the coding technique is known. Certain "pay-TV" systems are based on the payment of a fee for a device that is programmed for the particular coding technique being used so that the received signal can be used to generate a television picture.
Those systems have encountered a problem when the coded video signal is recorded by the subscriber using a video tape recorder (VTR). VTR's normally have noise reduction circuits to mask noise in the signal when it is played back. Unfortunately, noise reduction circuits can also mask information in the broadcast signal which is necessary for decoding the signal. Thus, when the recorded, encoded signal is played back through the receiver apparatus, it often will not be properly decoded.